(Phys.org) —Methane is the main component of natural gas, as well as a potent greenhouse gas whose levels in the atmosphere have been rising. In a new study, scientists have investigated a way to transform ...

A new study from scientists at the University of Miami Rosenstiel School of Marine and Atmospheric Science and colleagues confirms rising levels of water vapor in the upper troposphere – a key amplifier ...

Global warming is unequivocal, human influence has been the dominant cause since the mid-20th century, and atmospheric concentrations of greenhouse gases, already at levels not seen in at least 800,000 years, ...

An analysis of changes to the climate that occur over several decades suggests that these changes are happening faster than historical levels and are starting to speed up. The Earth is now entering a period ...

Planet hunters keep finding distant worlds that bear a resemblance to Earth. Some of the thousands of exoplanet candidates discovered to date have similar sizes or temperatures. Others possess rocky surfaces ...

The amount of solar radiation passing through Earth's atmosphere and reaching the ground globally peaked in the 1930s, substantially decreased from the 1940s to the 1970s, and changed little after that, a ...

the essential component of plastics—are found in countless commercial, medical, and industrial products. Polymers that are porous are called foam polymers and are especially useful because they combine ...

Gas

Gas is one of the three classical states of matter (the others being liquid and solid). Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point (see phase change), boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons are so energized that they leave their parent atoms from within the gas. A pure gas may be made up of individual atoms (e.g. a noble gas or atomic gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A gas mixture would contain a variety of pure gases much like the air. What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer. The interaction of gas particles in the presence of electric and gravitational fields are considered negligible as indicated by the constant velocity vectors in the image.

The gaseous state of matter is found between the liquid and plasma states, the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increased attention these days. High-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these exotic states of matter see list of states of matter.